Hi - I'm experimenting with a Beseler 23cII I just got. Exposure times are a little quick, even stopped down to f11 or f16, so I've been using a sheet of ND gel in the upper filter holder.
My question is this: can I use sheets of Ilford multicontrast filters and ND filters laying on top of each other in that upper filter stage and still get the right "behavior" out of the contrast filters?
Yes you can, and should. They are above the image forming area so the number of filters won’t impact image quality. I like the 0.6 ND filters because they cut the light a good amount without making it hard to see what you are doing.